The present invention relates to a work transfer apparatus for transferring works by a turn table which proximally rotates above a base.
FIGS. 3 and 4 respectively show a conventional work transfer apparatus.
As shown in FIGS. 3 and 4, a work transfer apparatus 1 includes a turn table 3 with a plurality of work-storing pockets 2 for storing works W at the outer periphery of the turn table and a base 4 which is proximal to the turn table 3 and slidably supports the works W stored in the work-storing pockets 2. A probing detector 6 is provided in the base 4 below a measurement point for measuring electrical characteristics of the works W, which is capable of protruding upwardly so as to come in contact with the works W in the work-storing pockets 2. An insulant material 5 for guiding the probing detector 6 is provided in the base 4 only at a portion where the probing detector 6 is provided.
In the work transfer apparatus 1 shown in FIGS. 3 and 4, the works W such as electronic components are stored in the work-storing pockets 2 and slid above the base 4 with the rotation of the turn table 3 to be transferred to the measurement point near the probing detector 6. When the works W are transferred to the measurement point near the probing detector 6, the probing detector 6 provided in the base 4 moves up and protrudes from the upper surface of the base 4 so as to come in contact with the works W. The electrical characteristics of the works W are thus measured by the probing detector 6.
To measure the electrical characteristics of the works W stored in the work-storing pockets 2 by the probing detector 6 provided in the base 4 as described above, the works W must be slid above the base 4. Accordingly, it is preferable that the portion of the base 4 which comes in contact with the works W has no step so that the works W may be smoothly slid above the base 4.
Namely, when any steps are generated at the portion of the base 4 which comes in contact with the works W, the works W transferred by the turn table 3 may be caught by the steps. Then, a problem occurs that cracks and breaks of the works W take place.
However, when providing the insulant material 5 for insulating a plurality of probes partially at the measurement point of the electrical characteristics of the portion of the base 4 which come in contact with the works W, steps may be generated on the base 4 by the insulant material 5. The following measures are taken to eliminate the steps on the base 4. That is, a spacer is used or a machining is applied to equalize the height of the insulant material 5 and that of the portion other than the insulant material 5 of the base 4.
However, even if the machining is applied, it is difficult to eliminate steps between the insulant material 5 and the portion other than the insulant material 5 because the hardness and the viscosity of the materials of the insulant material 5 and the portion other than the insulant material 5 are different from each other. Since the insulant material 5 has to be built in the base 4 without generating any steps, a built-in technique with high accuracy is needed whereby another problem arises that a manufacturing cost becomes expensive. Further, the insulant material 5 and the portion other than the insulant material 5 are worn out by using the work transfer apparatus 1, and steps may be generated between the insulant material 5 and the portion other than the insulant material 5 because of the difference in their degree of wear.
The present invention is made in consideration of the above disadvantages. It is an object of the present invention to provide a work transfer apparatus which has no step at a portion of a base which comes in contact with works, and is capable of transferring the works smoothly to a measurement point near a probing detector without the works being caught by the base when transferred.
The work transfer apparatus according to the present invention comprises a rotatable turn table with a plurality of work-storing pockets for storing works at the outer periphery of the turn table, a base slidably supporting the works stored in the work-storing pockets of the turn table, and a probing detector provided in the base, capable of protruding upwardly so as to come in contact with the works stored in the work-storing pockets wherein an entire portion of the base which comes in contact with the works is made of insulant material.
In the work transfer apparatus, the probing detector may be disposed in a hole portion provided in the insulant material constituting the base.
In the work transfer apparatus, the base may include an insulant material portion on the turn table side and a holding portion holding the insulant material portion.
In the work transfer apparatus, the insulant material portion may be made of a single insulant material.
In the work transfer apparatus, the insulant material portion may have a ringed shape.
According to the present invention, as the entire portion of the base which comes in contact with the works is made of insulant material, the insulant material portion is uniformly worn out as a whole during operation of the work transfer apparatus. Therefore, steps cannot be generated at the portion of the base which comes in contact with the works.